Two duct balloons were supplied on this project to provide auxiliary sealing of the existing inlet and outlet dampers during change out of the SCR catalyst elements. One balloon measured 47’0” wide x 12’0 high x 3’0” deep, and the other measured 44’0” high x 11’0” wide x 3’0” deep. The duct work ran in a vertical up position, so the balloons were installed on top of the existing dampers. The dampers were pinned closed, and the seal air systems were activated. Being that surface temperature of the dampers could not be verified, mineral wool insulation was installed on top of the dampers, and then the balloons were laid down on top of the insulation. Grab handles and “D” rings are sewn into the balloon to help maneuver the balloon in place during inflation. Inflation time for these large balloons is less than 10 minutes each.
Two 120V high pressure blowers were supplied using a “Y” type inflation tube near the connection point to the blowers. Due to its design, the duct balloon cannot become over pressurized by using two blowers simultaneously. In the event of a power loss to the one of the blowers, the balloon will remain fully inflated by the backup blower, as long as the blowers are connected to different circuit breakers.
Two 120V high pressure blowers were supplied using a “Y” type inflation tube near the connection point to the blowers. Due to its design, the duct balloon cannot become over pressurized by using two blowers simultaneously. In the event of a power loss to the one of the blowers, the balloon will remain fully inflated by the backup blower, as long as the blowers are connected to different circuit breakers.
This balloon measures 47’0” wide x 12’0” high x 3’0” deep (Damper Side)
Same picture showing inflation tube side (Note “D” Rings and Grab Handles)
Note the location of the inflation tube on this large duct balloon as it corresponds to the approximate location of the existing access door on the SCR reactor.
Copyright 2010 by G.R. Werth & Associates, Inc. - All rights reserved
Duct Balloon
Inflatable Isolation Barriers
